Pyrotechnic apparatus to assist in the tracking of aircraft

ABSTRACT

An apparatus for producing a smoke trail as an acquisition aid to operators of aircraft tracking cameras and tracking radar. A visually detectable trace is produced which enables the tracking operators to locate aircraft that they are required to track for data. The apparatus comprises a housing containing a plurality of pyrotechnic smoke devices suitably connected to a stepping relay so that on each application of a pulse of electricity by the aircraft pilot, the relay will sequentially ignite the pyrotechnic devices thereby forming a smoke trail. The smoke is formed from a mixture of hexachloroethane, zinc oxide, and aluminum.

United States Patent 1 Griffin et al. v

[ June 12, 1973 [54] PYROTECI-INIC APPARATUS TO ASSIST IN 3/1969 Fowler102/90 X THE TRACKING 0F AIRCRAFT I Primary Examiner-Benjamin A.Borchelt [75] T E' g i Assistant Egaminer-H. J. Tudor i SZ S Zi lAttorney-R. S. Sciascia and Thomas O.Watson, Jr.

[73] Assignee: The United States of America as [57] ABSTRACTrNepresented by the Secretary of the An apparatus for producing a smoketrail as an acquisiavy tion aid to operators of aircraft trackingcameras and 22 Fil d; N0 1 1970 tracking radar. A visually detectabletrace is produced which enables the tracking operators to locateaircraft {21] Appl. No.: 89,738 that they are required to track fordata. The apparatus comprises a housing containing a plurality ofpyrotech- 52 U.S. Cl. 102/87, 102/66 nlc Smoke devices Suitablyconnected to a pp 51 Int. Cl. F42b 13/34 relay so that on eachapplication of a pulse of electric- [58] Field of Search 102/87, '90,66, 6; ily y the aircraft pilot, the relay will sequentially ignite 0 355 the pyrotechnic devices thereby forming a smoke trail.

The smoke is formed from a mixture of hexachloroeth- 56 References Citedane, zincoxide, and aluminum.

UNITED STATES PATENTS 5 Claims, 1 Drawing Figure 3,109,821 11/1963 Yorket al....- 102/90 X 3,298,311 1/1967 Catlin 102/90 36 fl 211 q 28 3 4a2- 34 I 34 $1 26 I. la 32- a ga 20 so so 30 I4 PMENIEB m I 2 75INVENTORS WILL/AM c. GRIFFIN LYN/V BAR/(ER KENNETH R. FOTE m-romvzvPYROTECI-INIC APPARATUS TO ASSIST IN THE TRACKING OF AIRCRAFT STATEMENTOF GOVERNMENT INTEREST The invention described herein may bemanufactured and used by or for the Government of the United States ofAmerica for governmental purposes without the payment of any royaltiesthereon or therefor.

BACKGROUND OF THE INVENTION The present invention-relates generally topyrotechnic smoke devices and more particularly it pertains to anapparatus for producing a smoke trail as an acquisition aid to operatorsof aircraft tracking cameras and tracking radar.

burning a mixture of an organic dye with a fuel and an oxidizer from aspecial container within or attached to the aircraft or missile. Stillother prior art devices use flash powder which is activated by fuse toproduce a flash apparatus for use in signaling operations or in targetpractice. While such devices have been found satisfactory for the mostpart, there have been several disadvantages. For example, the devicesproviding an intense light source or those using organic dyes, fuel andoxidizer are unduly expensive for most tracking operations. In addition,the prior art devices require modification to the aircraft or missilefor mounting purposes or additional circuitry has to be provided toactuate the tracking devices.

OBJECTS OF THE INVENTION table device which is also' jettisonabl e fromthe aircraft.

SUMMARY OE THE INVENTION The general purpose of this invention is toprovide a smoke trail as an acquisition aid to photographic and radaroperators, wherein no aricraft modifications are needed to employ .theinexpensive, portable smoke generators of the present invention. Theinventive device may be simply mounted at the existing ordnance stationor bomb rack of the aircraft. Also, the existing arming circuit orfiring circuit of the aircraft is connected to a stepping relay withinthe smoke generator container.

This allows the pilot to actuate the smoke generators of the presentinvention in the same manner that a bomb would be armed from theaircraft. In addition, the inventive device is jettisonable from theaircraft, before or after all of the smokegenerators have burnt out.

Other objects, advantages and novel features of the invention willbecome apparent from the following detailed description of the inventionwhen considered in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING The drawing is a diagramatic view,partly in section, of the pyrotechnic tracking apparatus of the presentinvention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The drawing, whichillustrates a preferred embodiment of the smoke producing device, showsa smoke tank or cylindrical container 10 to house the entire assembly.The container 10 has a nozzle 12 formed within the forward end, the aftend 14 thereof being completely open. Fixedly attached within container10 is a rectangular support assembly 16 formed of aluminum channels.Longitudinal channels 18 and 20 extend beyond longitudinal channels 22and 24 in a forward direction and mount therebetween a stepping relay orintervalometer 26. Fixedly attached to the longitudinal channels 18, 20,22 and 24 are a plurality of vertical channels 28 and a plurality oftransverse channels 30 arranged to form a plurality of compartments 32.Although the preferred embodiment shows three such compartments, theinvention is not so limited, the number being dependent only upon theparticular use or need.

Mounted within each of the compartments 32 is a pyrotechnic smokegenerator or smoke pot 34, containing the chemicals hexachloroethane,zinc oxide, and aluminum which produce the smoke upon ignition. However,other materials which pyrotechnically form smoke may be used. A suitableelectrical ingition device is shown at 36, mounted within a hole 38formed in each smoke generator 34. Two leads (not shown) are providedfor each ignition device 36, one lead being connected to ground and theother lead connected to stepping relay 26.

In operation, the pilot of the aircraft can produce a smoke trail fortracking purposes by actuating the existing firing circuit or armingcircuit of the aircraft, which is connected to the stepping relay 26.Upon each application of a pulse of electrical current, the relay 26will sequentially ignite the smoke generators 34 thereby forming a smoketrail. The ignition sequence is aftcenter-forward with each smokegenerator 34 providing approximately 5 minutes of smoke at ambientpressure. The nozzle 12 is a novel feature of the present invention asit allows secondary air to enter container 10 which helps to expel thesmoke produced out of the aft end 14. Inaddition, this secondary airalso performs the function of keeping container 10 cool and at a safetemperature so that smoke generators 34 will not be ignited prematurely.Of course, the pilot need not ignite all of the smoke generators 34 onone flight pattern. For example, if desired, only one or two may beignited during one flight pattern, with the remaining ones being ignitedfor tracking purposes on another pass or flight pattern. In this manner,the apparatus of the present invention provides the pilot with completeflexibility and control. Accordingly, in the embodiment shown, eachcontainer 10 can produce a sustained 15 minute smoke trail if eachgenerator 34 is ignited immediatedly after the previous generator burnsout. Or if desired, 5 minutes of smoke may be produced, as needed, bythe pilots actuation of the stepping relay 26. Tracking personnel havereported very satisfactory results with the apparatus of the presentinvention when tracking flights were run" at altitudes up to 35,000 feethaving slant ranges of 2 miles to 25 miles and with the sky conditionsclear and cloudy.

Obviously many modifications and variations of the. present inventionare possible in the light of the above teachings.

' What is claimed is:

1. An apparatus adapted to be mounted on an aircraft to assist in thetracking thereof, which comprises:

a housing having an opening in the aft end;

a nozzle formed in the forward end of said housing;

a plurality of pyrotechnic smoke generators mounted within said housing;and

means for sequentially actuating said smoke generahexacholorethane, zincoxide, and aluminum.

* SI =l=

2. An aircraft tracking apparatus as recited in claim 1, wherein asupport assembly is mounted within said housing to support saidpyrotechnic smoke generators in a tandem arrangement.
 3. An aircrafttracking apparatus as recited in claim 2, wherein said smoke generatorseach have an electrical ignition device connected to said actuatingmeans.
 4. An aircraft tracking apparatus as recited in claim 3, whereinsaid actuating means is a stepping relay.
 5. An aircraft trackingapparatus as recited in claim 4, wherein said pyrotechnic smokegenerators contain hexacholorethane, zinc oxide, and aluminum.